performance enhancement for request rate limiter lua script.

[iis-MarkKuang]

Simplify request rate limiter lua script,
Regression tested with RedisRateLimiterLuaScriptTests.java.
Performance tested by stress testing on my own app, with lua script changes being the only variable.
For details please check issue #3681

[iis-MarkKuang]

I see the build fails on a test case that is not relevant to the change, are there any actions required to push the PR forward?
Run URL: https://github.com/spring-cloud/spring-cloud-gateway/actions/runs/13276014053/job/38594233165?pr=3693
TC class:

spring-cloud-gateway/spring-cloud-gateway-server/src/test/java/org/springframework/cloud/gateway/test/CustomBlockHoundIntegrationTest.java

Line 30 in a729fc0

public class CustomBlockHoundIntegrationTest {